Electrical instrument and system



Dec. 1s, 1.945. F. J. LINGEL 2,391,058

ELECTRICAL INSTRUMENT AND SYSTEM Original Filed Aug. 23 1940 3 Sheets-Sheet l INVENTOR flag/"(tiff [12W] ATTORNEY Dec. 318, 1945 F. J. LINGEL 2,391,053

ELECTRICAL INSTRUMENT AND SYSTEM Original Filed Aug. '23, 1940 5 Sheets-Sheet 2 Dec. 18, 1945. F. J. LINGEL ELECTRICAL INSTRUMENT AND SYSTEM 3 Sheets-Sheet 3 Original Filed Aug. 23, 1940 0 V w a M J Za'fffl ATTORNEYS INVENTOR Patented Dec. 18, 1945 ELECTRICAL INSTRUMENT AND SYSTEM Frederick J; LingelfBluflton, Ohio, asslgnor to The Liquidometer Corporation, Long Island City, N. Y., a corporation of Delaware Continuation of application Serial No. 353,783, August 23, .1940. This application December 12, 1944, Serial No. 567,848

Claims.

This invention relates to electromagnetic translating devices. More specifically, it relates to indicating instruments.

control is to be effected by a thermally responsive device, such as a resistance bulb.

The present invention is a continuation of my prior and copending application, Serial No. 353,783, filed August 23, 1940, and having the same title as the present application, said former application being now abandoned in favor of the present application. I

Some of the important objects of the invention are to provide devices of the type described which are compact, efiicient and reliable in operation.

comparatively simple in construction, and which may-be readily assembled and disassembled.

effect improvementsin the instrument disclosed in the said copending application.

Further objects are to provide novel forms of circuit connections embodying the improved instrument or instruments in combination.

Other objects and advantages of my invention will be stated hereinafter or will appear to those skilled in the art upon reading the following description of the invention and of the manner and process of making, constructing, compounding, and using it, and I shall also explain herein what I now believe to be the principle thereof, and the best mode in which I have contemplated applying that principle.

Desiring to have it understoodthat my invention may be carried out by other means and with other apparatus, and that it may be used in other environments and for other purposes, I shall now proceed to describe what I now consider to be a preferred form of apparatus for practicing the invention.

Referring to the drawings: Fig. l is a wiring diagram showing instruments so electrically connected one of my that fullcontrol and wide scale deflection may be obtained Fig. 4 is a section taken on a plane through the axis of an instrument embodying some of the features of the improvement.

Fig. 5 is a transverse section taken on the line 5-5 of Fig. 4.

Fig. 6 is a detail view of the coil mount forimng a part of the instrument S own in Figs. 4 and 5.

Fig.7 is an elevation of a compact composite instrument employing two of the instruments such as that shown in Figs. 4 to 6 but with the pointer or index of one offset so that both pointers may be read upon a single or common scale.

Fig. 8 is a fragmentary detail view showing an improved pointer construction which is shown also in Figs. 4 and 7.

Referring to Figs. 4, 5 and 6, it will be seen that the instrument there shown corresponds in many important respects to that shown and described in Figs. 2, 3 and 4 of my cited Patent No. 2,339,021, and I shall first describe the features of construction in common to the two and, later herein, points of departure and improvement.

The instrument shown in Figs. 4 to 6 comprises a rotor or armature it, which is permanently magnetized or poled transversely with respect to its axis of rotation or oscillation, a combined coil mount and damper l2, and a casing M which constitutes also a flux return path, magnetic shield, bearing support, and zero biasing means.

The rotor ill is preferably cylindrical and made of high coercive force material, such as Alnico, and is permanently magnetized so as to have a north pole on one side of the cylinder and a south pole on the other side substantially diametrically opposed to the north pole. The rotor it is secured to a shaft l8 coaxial with the rotor and rotatably mounted in bearings I8, l8, carried by the end nally adjustable in its plate 20, as by being screw threadedly connected therewith, loci: nuts 22, 22

being provided for holding the hearings in any position to which the bearings have been adjusted.

, Any rotation or oscillation of the rotor 18 produces corresponding movement of the shaft It.

While other forms 0! indicating means, such as a recording couple, may be utilized, I have shown an indicating couple consisting of a pointer 26 secured to a prolongation of the shaft 18 and a. suitably calibrated dial or scale 28, not shown in Fig. 4 but shown, in part, in Figs. 1, 2 and 3.

The coil mount I2 is constructed of a non-magnetic metal, such as brass, surrounds the rotor "and is surrounded by the casing M to which screws 30. The number of coils employed depends upon the particular use to which the instrument is to be put. The coils 32 are each so mounted that its flux axis intersects and is at a right angle to the axis of rotation of the rotor l and so that the flux axes of the coils intersect each other at an angled 120. The coil mount I2 is substantially of the shapeof a hollow cylinder and is slotted or cut away as shown (see especially Fig. 6) to form spools upon which the coils 32 are wound. Each spool portion of the coil mount I2 is provided with a slot 34 (see Figs. 4 and 6) through which the leads of the coil, mounted on that spool portion, extend. Before winding the coils on the spool portions, the coil mount I2, or

at least each spool portion thereof, is dipped in insulating material, such as Bakelite shellac or the like, which is then set or solidified by heating.

In winding, the starting end 38 of each coil 32 is stuck through the wall of a piece of flexible insulating tubing 36, such as a fabric tube or sleeve, mounted in the slot 34. After each coil has been wound, its finishing end 40 is stuck through the wall of another sleeve 36 so that the parts then appear as shown in the lower left hand portion of Fig. 4. The sleeves 36 thus provide quite satisfactory insulation, protection, and reinforcement for the leads of the coils.

The casing I4 is preferably made of cold rolled steel which is annealed after it has been machined. The casing is permanently magnetized or poled so as to have a north pole at one side and a diametrically opposed south pole on the other side, the poling being such that it will bias the permanently magnetized rotor 50 toward a zero or neutral position and cause it to occupy that position when the coils are all deenergized.

It will be noted that each of the coils 32 is embedded in the coil mount l2 and lies wholly to one side of the rotor l0. This facilitates assembly and disassembly of the instrument including insertion of the rotor l0 into, and removal of the rotor I 0 from, the instrument, without removing or in any way interfering with the coils 32, 32.

The coil mount I 2 serves as an effective low resistance eddy current damper for the rotor I0. Particularly is this so sincethis non-magnetic metallic coil mount occupies the space between the rotor I0 and the casing l4 except for the comparatively small portion thereof occupied by the coils 32, 32 embedded in the coil mount.

'I'hecasing i4 functions also as a support for the end plates and :bearings, as a return path for the magnetic flux, as'a magnetic shield, and as a biasing device for the rotor l0.

1 The instrument may be easily constructed, assembled, and disassembled. v

The instrument may be made quite compact and small. I have constructed a highly satisfactory indicatinginstrument embodying the invention in which the outside diameter of the casing I 4 is three-fourths of an inch and in which the distance between the end plates 20, 20 isthree-forths of an inch. I shall now proceed to describe differences between the construction shown in Figs. 4 to 6 hereof and that shown in Figs. 2 to- 4 of my cited patent, some of which differences are of greater importance than' others.

In my cited patent I showed only two coils 32 with their flux axes atan angle of 120, but

the specification of said patent stated that if pointer rotation of 360 or more were desired,

it is detachably secured by radially extending three or more coils equiangularly spaced about the rotor l0 would be employed. In the instant application, three such coils 32, 32, 32, are shown,

and each has its flux axis at right angles to the axis of rotation of the rotor l0, and the flux axis of each coil is at an angle of 120 withrespect to that of the adjacent coils 32, 32. In short, the three coils are so arranged that their flux 'axes .are equiangularly arranged around the axis of rotation of the rotor Ill.

In the cited patent, each end plate 20, 20, was shown detachably secured to a corresponding end of the casing l4 by means of screws 24. As shown in the instant application, only one of the end plates'20 is so connected to the casing it; the other end plate being integral with the casing l4 so as to provide a cup-shaped hous= ing which is closed by the other, and detachable,

. end plate 20. This provides a simplified construction.

' The tapped opening 240 shown at the upper The-pointer 26 is also of novel construction.

It comprises a metallic tube split throughout a portion of its length to form a hub or shaftreceiving portion 54 having two oppositely extending arms 56, 58, each :being one-half of a hollow cylinder. A metallic tube 60 is split, fiattened, and cut or stamped to form the index portion 62 and is secured at its opposite end to the arm 56. The last mentioned connection is effected by telescoping the tube 60 with the arm 66 and soldering or otherwise securing the two parts together.- The opposite arm 58 is shown screw-threaded'to receive the interiorly tapped counter-weight 34, thereby effecting an adjustable arrangement whereby the entire pointer 26 is balanced, i. e., has its center of gravity located on the axis of the shaft Hi. This construction of the pointer 26 provides a comparatively inexpensive, sturdy and light structure. I

As stated above, the casing I4 is preferably made of cold rolled steel which is annealed after it has been machined. A preferred heat treatment is as follows. The shell or casing I4 is heated to about 1600? F. in the absence of oxygen, soaked at 1600 F. for about two hours, and cooled at a rate not greater than about F. per hour to room temperature.

Because of its compactness and small size, the instrument shown in Figs. 4 to 6 lends itself admirably to constructions such as that shown in Fig. 7 in which it is desired to have two separately .controlled pointers read upon thesame single The lower ing the float.

izontally, as shown, so as to cause its index portion I62 to rotate in a plane below and parallel to the plane in which the upper index portion 62 rotates. The lower instrument is mounted on the bracket 66 in manner similar to the upper instrument and so that pointers 26 and I26 rotate about a common geometric axis. The two instruments, as stated, may be separately controlled but indicate upon a single dial. They may also be used as a comparison device. Because of the small size of the casings I I, I, the pointers 26, I26 may be kept comparatively short and therefore light in weight, sensititive, and with low moments of inertia. The particular pointer construction, by virtue of its light weight for the necessary sturdiness, also lends considerably to the desired result. In short, by virtue of the small size of parts which nevertheless produce and attain the required torque and mechanical strength, the double pointer common dial arrangement is rendered feasible and reliable under conditions of use which would otherwise prevent the attainment of that object.

In Fig. 1 I have shown one of my instruments so electrically connected and controlled by a single contact as to give a range of pointer deflection up to 360 in accordance with the position of the controlling contact. The contact 46 is shown connected to the arm 48 of a float 50 so as to assume different positions in accordance with the position of the float and, therefore, in accordance with the level of the liquid support- The instrument Ili-32-26-28 will be readily recognized as that shown in Figs. 4 to 6 and described above.

The electrical connections shownare as follows. The coils 32 are electrically connected together at one end. Three resistors 10, I0, I0

are electrically connected together at one end and to one side or pole of a suitable source of E. M. F. 12. The free end of each resistor 70 is electrically connected to the free end of a corresponding coil 32. The last mentioned (free) ends of the coils 32, 32, 32 and the resistors I0, I0, III are separately electrically connected to a flxed tap I4, another fixed tap l5, and a pair of manually adjustable taps'l6-18 of a resistor 80, respectively and as shown. The manually adjustable taps l6, l8 are electrically connected to each other. The float-controlled contact 46 is electrically connected to the pole or terminal of the source 12 opposite to that mentioned above.

By suitably selecting the electrical constants,

the combination shown in Fig. 1 may be emplayed to give a scale reading at 26-28 throughout the full 360 of movement of the pointer 26, the scale 23 being calibrated to indicate, in conohms. The E. F. of the source 12 is 12 volts.

In Fig. 2 I have shown a combination somewhat diflerent from that shown in Fig. 1. In the main, the instrument I0-32-26-23 is the same as'that shown in Figs. 1, 4, 5, 6 and described above. However, one of the coils 32 is wound in two sections I32, 232 which are so wound or connected as to oppose each other. II the coil 32, wound in twosections I32, 232 is disconnected from the circuit, the scale angle would be 120. By connecting coil 32 and by providing more turns. in one of the opposing sections I32, 232 than in the other of said sections, the full scale deflection of the pointer 26 may be made greater or less than 120 to an extent depending upon the difference between the numbers of turns in the two sections. When the number oi. turns of either section I32, 232 is greater than that of the other of said sections, the electrical connection of the differential coil 32 (I32-232) with respect to the other two coils 32, 32 determines whether the full scale deflection of the pointer 26 is greater or less than 120. If the predominant efiect of the coil combination (l32-232) is bucking with respect to the other coils 32, 32, the full scale deflection will be less than 120 to an extent,. as stated above, depending upon the difference between the numbers of turns of the two sections I32, 232. on the other hand, if the predominant effect of the coil combination (I32-232) is cumulative with respect to the other coils 32, 32, the full scale deflection will be greater than 120 to an extent depending upon the cliiference between the numbers of turns of the two sections I32, 232. I

The elements 46, 48, shown inFig. 2 will be recognized as being similar to the corresponding ance 83, hereinafter described) supplied by a suitable source of E. M. F. The float-controlled contact 46 is electrically connected to the outer end of the upper right hand coil 32 and to the inner end of the upper left hand coil 32. The outer end of the upper left hand coil 32 is electrically connected to the upper end of the resistor 82 and to junctlon'with the pointer 26, the remote liquid level at the float 60. By manually adjusting one or the other or both of the taps I6, 18, along the resistor 60, the deflection obtained at either or both ends of the scale 28 may be selectively adiusted or controlled. ture. of end scale adjustment, per se, is disclosed and claimed in United States Patent No. 2,195,813, patented April 2, 1940, Rheostat adjustment," Clarence A. de Giers.

While other constants or combinations of constants may be employed, satisfactory results may beattained with the following. Each coil 32 has 1600 turns and a resistance of 450 ohms. The resistance of each resistor I0 is 240 ohms. The resistance of the resistor 60 between the taps "-16 is 400 ohms, between the taps ll-I6 is 400 ohms, and between the taps Iii-Iris 400 This last mentioned tea-- the inner end of the composite coil 32 032-232). The inner end of the upper right hand coil 32 is electrically connected to the lower end of the resistor 82 and to the outer end of the composite coil 32 032-232).

Whatever the selected full scale deflection may be, the scale 28 is so calibrated and the design is such that the pointer 26' will indicate, upon the scale 28, the remote liquid level.

In order that short circuits across the line H2 at the transmitting station, or between the transmitting station and the indicating instrument, shall not damage the battery or so reduce its terminal E. M. F. as to render the operation of other instruments connected to the same line or source inaccurate and unreliable, I provide a protective resistance 83, mentioned above, and connected as shown. The resistance of this element 83 is such, with respect to the electrical constants of the rest of the system, as to prevent the undesirable consequences, spoken of above, that might otherwise result.

While other electrical constants may be employed, I have found that the following will give satisfactory results for a desired scale deflection less than The resistance of the resistor 82 is .200 ohms and that of the protective resistor 83 v is ohms. Each coil 32 has 1600 turns and a is twelve volts. In some cases and by proper selection oi'elecresistance of 450 ohms. One or the coil sections I32, 232 has 900 turns and the other IOU-turns, with'the predominant efiect bucking with respect to the other two coils 32, 32. The E. M. F. at 2 trical constants more than one indicator may be reliably controlled by the same transmitter by connecting the indicating instruments in parallel. For example, in the arrangement shown in Fig. 2 and' with the electrical constants as above set forth, a second instrument identical to the instrument l28-- 28-3Z-83 may be electrically connected in parallel, therewith across the leads or conductors and the positive line 12. Bella bility inindication has been attained in suchuse of a plurality of indicating instruments by virtue of the comparatively high resistance 01' the coils 32, 32, 32 (132-233) with respect to the resistance of the potentiometer or resistor 82. Also, in the arrangement shown in Fig. 1, and with the electrical constants as set forth in connection with the said Fig. 1, a second instrument identical to the instrument l0-26--28'-32-'|0 may be electrically connected in parallel therewi 11 across the leads or conductors which are connected to the taps l4, 15, 16-18, and to the upper sid of the source 12. In the above described systems, the control element at the transmitting station has been shown as. a movable element 48. The indicating instrument maybe controlledby other devices such as. a resistance bulb. Such a control is shown in Fig. 3, which nectionsc 1 In Fig. 3, the resistora92, 84, and 86 constitute shows also different electrical con- ,ILM.

discs would appear as indicated in the central part 01' Fig. 5.

In accordance with .the rovisions of the patent I binations and relations described, some of these may be altered and others omitted, and some ofthe features of each modification may be embodied in the others, without interfering with the more general results outlined, and the invention 4 extends to such use within pended claims.

What I claim is:

1. An indicating instrument including a perthe scope or the applurality of coils angularly spaced around the rotor for actuating said rotor to various positions throughout substantially 360, a source oi an electrical circuit for said coils includvariable element, said variable element selectively determining the relative strength of current supplied to said coils from said source of 1 'ing one of. the coils, one end of each having a common connection.

three armslof. a bridge circuit of which the fourth arm is a resistor bulb or thermally responsive element indicated diagrammatically at 88. The instrument l0262832 will be recognized as the same as that above described in connection with Fig.1 but has its coils connected differently. One coil 32 is connected across the bridge at m2,

l02;'and the other two coils 82, 32 are connectedin the manner illustrated, across the battery or source of E. M. F. 12. The battery is connected across the bridge circuit at 900, Hill.

The resistance of the device 98 depends upon the temperature of the medium surrounding it and varies in. accordance with changes in temperature. .The' scale 23 may therefore be so callbrated that the pointe'r'll-will automatically indicat the temperature at the transmitting station. i

It will now be seen that my novel instrument shown in Figs. 4,5 and 6 lends iseli to useln a variety of combinations (some of which are also novel) withoutany change in the instrument other thanin the electrlcalconnections of. the coils 82. By providing one of the coils 32 with separate windings and suitable leads, the some instrument shownin the other figures of drawings may also be employed in the combination shown in Fig. 2. Thus, the number or instruments required to be kept instock for a purposes and uses. is minimized. It is to'be understood that netized rotor wide-variety oi discs or sections or the rotor [0 (Fig. 4)' is so mounted and permanently magnetizedz;or poled make electrical contact that the lines connecting the opposite poles or each of the four sections lie in a single plane-containing the geometric axis of the' rotor. In other words, a transverse section or any oi the tour I mitter response to variations, "transmitted, the

said circuit including a plurality of resistors each connected at one end to said source of E. M. F. and at its other end to a correspondof said coils '2. An indicating instrument including a permanently magnetized rotor and a plurality of coilsangularly spaced around said rotor and each having its axis radial with respect to said rotor, a plurality of resistors each connected at one end to a corresponding one of said coils, the other ends of said coils being electrically connected together, a source of E. M. F., means electrically connecting the ends of said resistors opposite said first mentioned ends to said source oi E. M. F., and means including a variable resistance connected to said coils and resistors for .-manently magnetized cylindrical rotor and. a

controlling the supply of current to said coils from said source of E. M. F

3. A telemetering system comprising a transmitter, a receiver, a set cit-resistors and conductors joining the transmitter to the resistor set and the receiver, the transmitter comprising an electrically continuous resistor with three terminals connected thereto and a brush adapted to make contact with points along the resistor in accordance with the indication to be transmitted,

the receiver comprising a plurality of currentconducting coils and. a unidirectionally magrotatable .in response to variations in current distribution in the receiver 'coils, said coils being star-connected to the terminals 01' the transmitter resistor, the said resistor set also being star-connected to the transmitter resistor terminals and having a neutral point adapted to be connected to one terminal 01' a current source,"

terminal transmitter brush.

0! which is connected to the- QA telemetering system comprising a transmitter. a receiver and a set of resistors, the transcomprising a resistor having a plurality of terminals and a movable brush adapted to with various points in resistor set comprising a plurality oi resistors star-connected to the terminals. of the transmitterresistor and'having a in .the indications to be tribution in the receiver winding, said windings being star-connected with terminals connected to the resistor set.

5. A telemetering system comprising a transmitter, a receiver and a set of current-distributing resistors, said transmitter comprising a re sistor with a plurality of terminals and a brush It is here by certified that err er the above numbered patent requiring" correction as fOlIGNS:

4 CERTIFICATE -or CORRECTION.

- FREDERICK J. LINGELL adapted to make contact with diflerent points on the resistor in response to variations in an indication to be transmitted, the said set. of resistors comprising a plurality of resistors star-connected to the terminals of the transmitter and having a neutral terminal, the said neutral terminal and the transmitter brush being adapted to be connected to a current source, the receiver comprising current-conducting windings and a magnetic rotor movable in response to variations in current distribution in said windings, said windings having a plurality of terminals star-connected to said resistor set.

FREDERICK J. LINGEL.

December 18, 9 -5 or appears 1n; the printed specification Page 5, first column, line 15, for "'se nsititive" read sensitive"; line 72, for the and that the said Letters Pat nt should be: read with this correction therein, that the same may conform to the record of "the case in the Patent Office.

' Signed an sealed this 19th day (SeaI) of February, A; a. 19%.

Leslie Frazer 

